Malignant Colon Polyps

A “malignant” polyp is defined as the presence of adenocarcinoma that extends beyond the basement membrane. It is important to assess specific characteristics of the polyp in order to decide whether further, more aggressive treatment is needed for adequate removal. Invasive polyps can be pedunculated or sessile. Pedunculated polyps contain a head, neck and stalk whereas sessile polyps are flat. In addition to the morphology of the polyp, important histopathological features including grade of differentiation, the presence of lymphovascular invasion, perineural invasion or tumor budding as well as inadequate resection margins (<2 mm) all play a very important role in predicting more aggressive disease in invasive polyps.